This application is related to U.S. disclosure document No. 468,068, filed Jan. 27, 2000.
My present invention generally relates to intercropping of commercial plants. More specifically, my invention is a process by which legumes such as soybeans are alternated in rows with wild species and/or totally domesticated species such as buckwheat or corn.
My invention in the preferred embodiment and best mode is intended for commercial machine-driven agricultural methods. It is an advantage economically that my method incorporates the commercially successful conservation tillage system in the present United States. This is especially true in the Midwestern and prairie states. However, methods using hand implements for smaller suburban or urban plots with, for example, vegetable gardens are also within the scope of my invention.
A legume is a plant whose roots form an association with soil bacteria which capture and fix atmospheric nitrogen (N2). These plants generally form nitrogen fixing nodules on their roots under appropriate growing conditions. Atmospheric nitrogen N2 cannot be used by crops, even though the atmosphere is approximately 70 to 80% nitrogen in this form. Fortunately, nodules on legume roots can change N2 to nitrogenous compounds, which can be absorbed by crops through the soil. In the United States, farmers plan soybeans for nitrogen fixing, as well as for forage and commercial purposes. However, other nitrogen fixing plants, known generically in the industry as xe2x80x98green manurexe2x80x99 (such as buckwheat), are also satisfactory.
Use of legumes to replenish soil nitrogen has been well known for centuries by those well versed in the agricultural art. Similarly, it has long been known that corn and soybeans successfully grow together under certain conditions, and that soybeans prevent rapid depletion of soil nutrients by corn.
My method for intercropping also incorporates the above described ecological benefits of intercropping a commercially successful annual legume such as soybeans, and a second commercial annual grain-crop such as corn. xe2x80x9cIntercroppingxe2x80x9d is generally defined among farmers and agricultural scientists as: the planting of a fast growing crop between rows of a slow growing crop.
My method in its best mode need not include pesticides and herbicides to obtain healthy plants. Instead, my method in which corn and soybeans are planted at approximately the same time, insures effective ground cover and erosion resistance, in addition to grain production and soil enrichment. In the prior art soybeans, which can also be a cash crop, are generally plowed into the soil at the first frost. There they remain to decompose and release usable nitrogenous compounds in the soil for the next series of crops.
Using my improved method, there is increased drought resistance through an effective ground cover and subsoil root network, as well as an effective moisture canopy and windbreak. Moreover, my method provides a crucial development period for both soybean and corn seedlings through a microclimate effect. The fixation.of atmospheric nitrogen N2 by legumes also benefits associated plants.
My process differs in that although the soybean pods are harvested early in the growing seasons, the roots and stems are left intact to provide ground cover. There also remains a subsoil root retention system during the winter months and following spring planting season.
Crops such as corn and potatoes benefit from this approach, as long as planting time is properly synchronized with that of the soybeans. The young plants cling to soybean residues and provide an anti-erosion network.
There are prior art approaches to planting annual grain crops in a predetermined fashion in one growing area. U.S. Pat. No. 5,140,917 (Swanson) describes a method and apparatus for seeding agricultural crops. In this method, seeds are placed in residue free rows which are closed aligned and associated with bands of deeply placed fertilizer. The plants from each seed are claimed to access more than one deep band of fertilizer. There is no intercropping component to Swan""s model, however European Application 0132521 (Hilmer) describes intercropping with two or more crops on one piece of land per seasonal growing year. He uses the grass/grain cluster/per row or a modular cluster row planter upon a slope contour.
U.S. Pat. No. 4,084,522 (Younger) describes a method by which soybean seeds are sown into a standing grain crop (e.g. wheat). When the grain crop is ripe, it is harvested by a combine at a height which is slightly greater than the height of the partially grown soybeans.
Unlike my process, however, in Younger""s model the wheat is planted first, while corn and soybeans are planted considerably later during the same growing season.
U.S. Pat. No. 6,009,955 (Tarver III) is based upon the size and shape of furrows created by a modified harvesting machine. The planter creates these furrows just prior to planting or during the planting season.
Koch described corn planted in 30 inch rows with application of insecticides and liquid nitrogen fertilizer. There is a legume ground-cover such as vetch or clover. According.to this report, clover did not demonstrate potential as a perennial cover crop. Phillip Koch, xe2x80x9cLegume Cover Crops for No-Till Cornxe2x80x9d in J. F. Power, THE ROLE OF LEGUMES IN CONVERSATION TILLAGE SYSTEMS (1984).
Decker et al. describes winter legume cover crops which were seeded after fall corn harvests, and which were allowed to grow until corn planting the following spring. Results indicated that fall-seeded legumes can at least partially replace artificial nitrogen fertilizers for maximum corn yields. A. M. Decker et al., xe2x80x9cFall Seeded Legumes"" Nitrogen Contributions to No-Till Corn Production,xe2x80x9d in J. F. Power, supra.
Holderbaum reported results with legume cover crops in which legumes were grown prior to corn, but later during the same growing season. In this model the legumes were clover and ryegrass. According to this investigation, subsequent corn grain yields were highest when the cover crop was not removed. J. F. Hauderbaum et al., xe2x80x9cForage contributions for winter legume cover crops in no-till crop production,xe2x80x9d in J. F. Power, supra.
Scott and Burt reported intercropping red clover into corn seedlings when the corn seedlings were approximately six to twelve inches high. The scientists applied chemical herbicides to the seedlings during this investigation. According to Scott and Burt, good crops were consistently obtained by cultivating corn in a 30 inch row. Intercropping occurred when corn seedlings were approximately 12 inches in height. High corn yields consistently occurred following the plowdown of one year of red clover hay.
Scott and Burt concluded that red clover or other legume establishment by intercropping into corn might become a beneficial management approach for nitrogen replenishment, organic matter addition and reduced erosion. T. W. Scott and Robert F. Burt, xe2x80x9cUse of Red Clover in Corn Polyculture Systems,xe2x80x9d in J. F. Power, supra.
Paudey and Pendleton reported the planting of corn seed in 1.5 meter rows with corn seedlings spaced approximately 17 centimeters apart. Three rows of soybeans were planted between single rows of corn. The investigators applied herbicides and pesticides to the seedlings during the experiments. Forty-two days after planting, the two most exterior soybean rows were ploughed into the cornrows in a traditional xe2x80x98hilling upxe2x80x99 procedure. R. K. Paudey and J. W. Pendleton, xe2x80x9cSoybeans as a Green Manure in a Maize Intercropping System,xe2x80x9d EXPERIMENTAL AGRICULTURE 22:178-85 (1986).
Eadie et al. reported the effect of cereal cover crops upon weed control. The investigators hand planted cereal seed within plots which were approximately 2.3 meters wide and 8.0 meters long. The rows were approximately 0.75 meter equidistantly spaced. The investigators seeded the cereal cover crops immediately after the ridging cultivation at the 11-12 leave stage of cornplants.
According to the Eadie report, corn grain yields remained unchanged by cover crops seeded at the 11-12 leaf stage of corn, compared to bare soil treatment controls. Allan G. Eadie et al., xe2x80x9cIntegration of Cereal Cover Crops in a Ridge-Tillage Corn Production,xe2x80x9d WEED TECHNOLOGY 6 (3) (July-September 1992).
Lesoing and Francis stripcropped corn and soybeans to reduce erosion in eastern Nebraska from 1988 to 1990. Corn and soybeans were no-till planted in a north-south orientation in alternating 6.1 meter wide strips (eight rows, 0.76 meter between rows). Each row was approximately 46 meters in length, and each experimental planting areas comprised approximately 280 square meters.
Lesoing and Francis planted pioneer corn weed at a density of approximately 66,250 seeds/ha. Between the corn strips they planted soybean seedlings in strips of eight rows at 475,000 seeds/ha. Corn border row yields next to soybeans increased significantly compared with interior rows. These scientists suggested that water stress, light quality and shading are among the factors which affect crop yields at different stages of crop development. Gary W. Lesoing and Charles A. Francis, xe2x80x9cStrip Intercropping Effects on Yield and Yield Components of Corn, Grain, Sorghum and Soybean: AGRONOMY J. 91: 807-13 (1999).
One farmer has reported that closer planting in rows allows more equitable distribution of sunlight, soil moisture and nutrients. NO TILL FARMER (mid-January 1986).
My new improved intercropping process solves a longstanding problem in agriculture and in the ecology generally.
Soil becomes depleted of nutrients and then eroded. Productivity for an increasing world population of people and domesticated animal decreases every year. My observation of legumes intertwined with growing crops indicates many advantages of my new intercropping process, including: A reliable source of soluble nitrogen compounds in the soil, additional humus, and prevention of erosion by underground and above ground soybean residues.
My novel method intercrops soybeans and corn in a conservation tillage situation. Corn and soybeans are planted on or about May 1, when the preferred soil temperature is approximately 60 degrees F. By growing in a non-herbicide, non-pesticide, non-irrigated area, corn and soybean plants generate a leaf canopy and an intertwining root system.
Legume nodules on the soybean roots appear shortly after root growth begins during that particular growing season. The crop leaf canopy also demonstrates a shading effect and anti-erosion effect on soil. In the preferred embodiment and best mode, planting of soybeans between cornplants is a necessary component of my novel planting method.
Another component of my invention comprises the process of planting fields or gardens in alternating rows or in other configurations, of two or more kinds of crops. In the preferred embodiment, the predetermined alternating rows and areas comprise corn or soybeans. Each crop can be in straight lines, or in curved or convoluted alignment, according to the geography of the planting area.
In the preferred mode and best embodiment, soybeans are spaced a predetermined distance from each other and each adjacent corn row. Corn and soybean roots extend approximately four feet into the soil, and intertwine at approximately four to six weeks into the growing season. For other models, conventional cash crops such as corn and buckwheat alternate with plants such as Queen Anne""s lace, vinegar weed, Pennsylvania smartweed, wild grasses or cornflowers. These last named plants are often considered predominantly weedlike in nature.
Sweet clover and perennial grass are also candidates, and all the above combinations are within the scope of my invention. Other possibilities, although not exclusive, include corn and potatoes, corn and peanuts or peanuts and soybeans. The alternating configuration of crops and other appropriate plant species also provides protection against insect pests. Insects can no longer eat from once side of a field to the other, because other specially selected crops act as ecological barriers.
Moreover, by using my new planting process, edible yields are greater for the same two dimensional or three dimensional section of a field or garden. For maximum yield over a given area, crops are combined in a single bed.
Intercropping is the method of growing quick-maturing vegetable crops between slower developing crops, and maximizing use of available garden or field space. Soybeans are planted in spring or summer at 2 to 3 lb of seeds per 1,000 square feet in traditional commercial situations. Soybeans are annuals and must be reseeded every year; however, they tolerate poor drainage well, and are ideal for nitrogen fixation. Moreover soybeans, adzuki and muny beans are fairly resistant to insect pests.
Consequently, one goal of my improved intercropping method is to prevent desiccating winds from harming crops.
Another goal of my improved intercropping method is to insure that the soil is always saturated with the correct amount of organic nitrogenous residue.
Another object of my invention is to adapt my soybean corn model to a commercial model for agriculture, using a combine for tillage and drilling devices for seeding corn and soybeans.
Another goal of my invention is to add ground cover to fields which are generally uncovered and fallow.
Another goal of my invention is to decrease soil exposure to erosion from sun, wind and running water.